Socket.IO

Socket.IO is a Node.JS project that makes WebSockets and realtime possible in
all browsers. It also enhances WebSockets by providing built-in multiplexing,
horizontal scalability, automatic JSON encoding/decoding, and more.

How to Install

npm install socket.io

How to use

First, require socket.io:

var io =require('socket.io');

Next, attach it to a HTTP/HTTPS server. If you're using the fantastic express
web framework:

Sending volatile messages.

Sometimes certain messages can be dropped. Let's say you have an app that
shows realtime tweets for the keyword bieber.

If a certain client is not ready to receive messages (because of network slowness
or other issues, or because he's connected through long polling and is in the
middle of a request-response cycle), if he doesn't receive ALL the tweets related
to bieber your application won't suffer.

In that case, you might want to send those messages as volatile messages.

License

Permission is hereby granted, free of charge, to any person obtaining
a copy of this software and associated documentation files (the
'Software'), to deal in the Software without restriction, including
without limitation the rights to use, copy, modify, merge, publish,
distribute, sublicense, and/or sell copies of the Software, and to
permit persons to whom the Software is furnished to do so, subject to
the following conditions:

The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.